The present embodiment improves upon three previous approaches: two of which are set forth in U.S. Pat. Nos. 5,404,869 and 5,676,453, both by Parkyn & Pelka, being continuations in part of the first, U.S. Pat. No. 4,337,759 by Popovich, Parkyn, & Pelka, which are herein Incorporated by reference. These patents describe Totally Internally Reflecting (TIR) lenses with circular, toroidal, or cylindrical symmetry that produce output beams normal to an exterior surface.
The prior devices disclosed in U.S. Pat. Nos. 5,404,869, 5,676,453, and 4,337,759, Incorporated herein by reference, have outputs that are inherently aligned with a system axis of symmetry. Previously, slanted beams required an external means, typically auxiliary external faceting, which has the disadvantages of dust collection, increased device thickness, non-conformity with any adjoining exterior surface, and lost lens efficiency.